A comprehensive investigation of tetragonal Gd-doped BiVO ₄ with enhanced photocatalytic performance under sun-light

Tetragonal Gd-doped BiVO ₄ having enhanced photocatalytic activity have been synthesized by a facile microwave hydrothermal method. The structural analysis indicates that Gd doping can induce the phase transition from monoclinic to tetragonal BiVO ₄ . The reaction results in precursor solutions imply that tetragonal GdVO ₄ seeds as crystal nucleus are the original and determined incentives to force the formation of tetragonal Gd-BiVO ₄ . The influences of the surface defect, band structure, and BET surface area on the improved photocatalytic activities of tetragonal Gd-doped BiVO ₄ are investigated systematically. The results demonstrate that the more surface oxygen deficiencies as active sites and the excellent mobility and separation of photogenerated electrons and holes are beneficial to the enhancement of the photocatalytic performance of tetragonal Gd-BiVO ₄ . The RhB photodegradation experiments indicate that the contribution of high photocatalytic activities under simulated sun-light is mainly from UV-light region due to the tetragonal structure feature. The best photocatalytic performance is obtained for tetragonal 10 at% Gd-BiVO ₄ , of which the RhB degradation rate can reach to 96% after 120 min simulated sun-light irradiation. The stable tetragonal Gd-BiVO ₄ with efficient mineralization will be a promising photocatalytic material applied in water purification.